Role of TBK1 polyubiquitination in innate antiviral immunity

TBK1 多聚泛素化在先天抗病毒免疫中的作用

• 批准号: 8108823
• 负责人: MARTIN E DORF
• 金额: $ 54.05万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8108823
• 关键词: Accounting; Antiviral Agents; Antiviral Response; Autoimmunity; Base Pairing; Binding; Cells; Chronic; Containment; DNA; Data; Dendritic Cells; Development; Disease; Double-Stranded RNA; Fibroblasts; Gene Expression; Genes; Genetic Transcription; Genomics; Grant; IRF3 gene; Immune response; Immune system; Immunity; Immunologic Deficiency Syndromes; In Vitro; Infection; Infection Control; Inflammatory; Injury; Interferons; Invaded; Ligands; Ligase; Link; Malignant Neoplasms; Mediating; Medical; Microbe; Mind; Modeling; Modification; Molecular; Mus; Natural Immunity; Nucleic Acids; Pathway interactions; Pattern; Pattern recognition receptor; Phagocytosis; Phosphotransferases; Play; Polyubiquitination; Post-Translational Protein Processing; Predisposition; Process; Production; Proteins; Proteomics; RANTES; RNA Interference; RNA Viruses; Regulation; Reporter; Resistance; Role; Series; Signal Pathway; Signal Transduction; Site; Sting Injury; System; TBK1 gene; TLR3 gene; TLR4 gene; Testing; Touch sensation; Ubiquitin; Ubiquitination; Vesicular stomatitis Indiana virus; Viral; Virus; Virus Diseases; Work; antimicrobial; base; cell type; cytokine; disorder prevention; helicase; human IRF3 protein; induced pluripotent stem cell; insight; interferon regulatory factor-3; irritation; macrophage; microbial; novel; overexpression; pathogen; protein complex; prototype; receptor; research study; response; sensor; therapy design; transcription factor; tripolyphosphate; ubiquitin-protein ligase; viral RNA

DESCRIPTION (provided by applicant): Innate immunity is the first-line of defense used by all types of cells to protect against invading microbes. Defense against microbial attack is critically important for the entire body and touches far-ranging medical domains. Properly regulated antimicrobial responses control infection and limit the effects of injury and irritation. When these processes go awry - because the response is too weak, too strong or misplaced - the result may be immunodeficiency, autoimmunity, or cancer. Studies of innate antiviral immune responses have been highly influenced by the discovery of the IKK-related kinase, TBK1. Substrates for TBK1 include the transcription factor interferon regulatory factor (IRF)-3, which controls transcription of type 1 interferons (IFN). This proposal investigates the molecular mechanisms underlying TBK1-dependent transcription of IFN and other antimicrobial cytokines. Our preliminary data identify two E3 ubiquitin ligases which target TBK1 for K63-linked polyubiquitination (pUb), control TBK1 kinase activity, regulate IRF3 signaling, and protect against viral infection. Specific Aim 1 analyzes TBK1 pUb including characterization of the E3 ligases and identification of TBK1 Ub acceptor sites. As background we provide evidence that TBK1 is posttranslationally modified by K63-linked pUb chains in a ligand dependent fashion. We also supply data indicating a role for mind bomb (MIB) proteins in regulating TBK1 pUb and IFN production. This is the first evidence that the E3 ligases MIB1 and MIB2 participate in IRF dependent responses. Specific Aim 2 investigates the consequences of MIB1 and/or MIB2 deficiency on IFN production and protection against viral replication. Initial experiments have reassuringly supported a role for mib genes in protection against vesicular stomatitis virus (VSV). Specific Aim 3 will examine the requirements for MIB-mediated TBK1 pUb in response to RLR and TLR ligands or in response to dsDNA in fibroblasts, macrophages, and dendritic cells. The final Specific Aim will identify TBK1 associated molecules which regulate the RLR, TLR3, TLR4, or dsDNA signaling pathways. The molecular mechanisms controlling the assembly of TBK1 signalosomes will be determined. Our recent data suggest a novel hypothesis accounting for MAVS-dependent TBK1 activation; the proposed studies will test and expand upon this model. Detailed descriptions of the molecular interactions that regulate TBK1 activity are important since dysregulation of this kinase is associated with susceptibility to viral infection and other diseases. Insights from the proposed studies may ultimately facilitate design of therapies that may curtail IKK-related pathways in chronic inflammatory diseases or enhance TBK1 activity when needed to boost immunity. PUBLIC HEALTH RELEVANCE: Recognition of viral nucleic acids activates the innate immune system to produce interferon and other antiviral proteins, thereby granting resistance to viral replication. This proposal examines the signaling mechanisms responsible for interferon production in defense against microbial infection.

描述（由申请人提供）：先天免疫是所有类型的细胞用于防止入侵微生物使用的防御的第一线。防御微生物攻击对于整个身体至关重要，并触及了远程的医疗领域。适当调节的抗菌反应控制感染并限制损伤和刺激的影响。当这些过程出现问题时 - 由于反应太弱，太强或放错了位置 - 结果可能是免疫缺陷，自身免疫性或癌症。与IKK相关激酶TBK1的发现，对先天抗病毒免疫反应的研究受到了极大的影响。 TBK1的底物包括转录因子干扰素调节因子（IRF）-3，它控制1型干扰素的转录（IFN）。该建议研究了IFN和其他抗菌细胞因子的TBK1依赖性转录的分子机制。我们的初步数据鉴定了两个E3泛素连接酶，它们靶向TBK1用于K63连接的多泛素化（PUB），控制TBK1激酶活性，调节IRF3信号传导并预防病毒感染。特定目标1分析TBK1 Pub，包括E3连接酶的表征和TBK1 UB受体位点的鉴定。作为背景，我们提供了证据，表明TBK1是通过配体依赖性方式通过K63连接的酒吧链在翻译后修饰的。我们还提供了指示思维炸弹（MIB）蛋白在调节TBK1酒吧和IFN产生中的作用的数据。这是E3 Ligases MIB1和MIB2参与IRF依赖性响应的第一个证据。具体目标2调查了MIB1和/或MIB2缺乏对IFN产生和防止病毒复制的影响。最初的实验令人放心地支持MIB基因在保护囊炎病毒（VSV）中的作用。具体的目标3将检查对RLR和TLR配体的MIB介导的TBK1 Pub的要求，或响应成纤维细胞，巨噬细胞和树突状细胞中DSDNA的要求。最终的特定目的将识别TBK1相关的分子，这些分子调节RLR，TLR3，TLR4或DSDNA信号通路。将确定控制TBK1信号体组装的分子机制。我们的最新数据表明，一个新的假设占MAVS依赖性TBK1激活。拟议的研究将测试和扩展该模型。调节TBK1活性的分子相互作用的详细描述很重要，因为该激酶的失调与病毒感染和其他疾病的易感性有关。拟议研究的见解最终可能有助于设计疗法，从而减少慢性炎症性疾病中与IKK相关的途径，或者在需要时增强TBK1活性以提高免疫力。 公共卫生相关性：识别病毒核酸的识别激活了先天免疫系统，以产生干扰素和其他抗病毒蛋白，从而赋予对病毒复制的抗性。该提案研究了负责防御微生物感染中干扰素产生的信号传导机制。